* {
  padding: 0;
  margin: 0;
}

.info {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  padding: 10px 20px;
  background: rgba(0, 0, 0, 0.3);
  color: #fff;
  border-radius: 5px;
}

.introduction {
  position: fixed;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  padding: 40px;
  width: 560px;
  line-height: 30px;
  background: rgba(0, 0, 0, 0.8);
  color: #fff;
  border-radius: 5px;
  z-index: 99;
}

.introduction h4 {
  text-align: center;
  line-height: 40px;
}

.introduction button {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #fff;
  border: none;
  color: #000;
  padding: 5px 10px;
  border-radius: 5px;
  cursor: pointer;
}
